How to access to the functions list from the interface? In a channel > "Attributes Matching" > from each channel field > "How to fill in this value? " tooltip > "Need function?" link
1. Text functions
Syntax: UPPER($text_field)
Example: I want all the characters sent to the channel field "title" to be in capital letters.
Syntax: LOWER($text_field)
Example: I want all the characters sent to the channel field "title" to be in lowercase.

UPPERWORD: Capitalizes the first letter in a text string and any other letters in text that follow any character other than a letter
Syntax: UPPERWORD($text_field)
Example: I want the first letter of each word to be a capital, in the channel field "title".
Syntax: UPPERSENTENCE($text_field)
Example: I want each sentence to begin with a capital, in the channel field "title".
Syntax: TRUNC($text_field,number of characters)
Example: I want to limit my description to 2,000 characters.
Syntax: SMARTTRUNC($text_field,number of characters)
Example: I want to limit my description to 2,000 characters without cutting off the last word.
Syntax: STRIPHTML($html_text_field)
Example: I want to remove the html tags from my description.
Syntax: URLENCODE($text_field)
Example: I want to add the title of my products in the tracking of my URL products.
2. Mathematical functions
Syntax: ROUND(number to round up/down,number of figures desired after the decimal point)
Round up/down the number, to the nearest tenth, hundredth...of a decimal number, cutting down to the stated rank then:
 if the following number is 5, 6, 7, 8 or 9, you increase the last figure of the cut number by 1.
 if the following number is 0, 1, 2, 3 or 4, you keep the cut number.
To round up to a whole number, mark "0" as "the number of figures desired after the decimal point" or mark ROUND(numbertoround).
Example:
 To round a price to two figures after the decimal point: ROUND($field_price,2) > If my price is "14.1576" in my product catalogue, it becomes "14.16".
 To remove decimals of quantity values: ROUND($field_quantity,0) or ROUND($field_quantity) > If my quantity is "4.000" in my product catalogue, it becomes "4".
Syntax: ROUNDUP(number to round up to the nearest whole number)
Example: I want to round my price up to the nearest whole number:
Syntax: ROUNDDOWN(number to round down to the nearest whole number)
Example: I want to round my price down to the nearest whole number:
 Divide: CALC(number1/number2)
 Multiply: CALC(number1*number2)
 Addition: CALC(number1+number2)
 Subtraction: CALC(number1number2)
"number1" and "number2" can be replaced by "$my_field"
With the assistance of brackets, any calculation can be performed. The function performs the calculations in order of priority.
Example: I want to calculate the reduction percentage of my reduced products.
I want to increase my sales price by 10%, round it up to the nearest whole number, and subtract 10 cents.
I want to reduce my sales price by 15% and add my shipping costs increased by 5%.
Syntax: CURRENCYCONV(price,iso_code)
Example: I want to convert a price into GBP.
Conversion rates are based on the European Central Bank (ECB) and are updated once a day.
3. Concatenate several functions
Combine as many functions as you like whilst playing with the brackets!
Example: I want to increase my sale price by 10% and round the result by two figures after the decimal point
Example: I want to limit my description to 2,000 characters and write the text in capitals.
Example: I want to increase my sales price by 10% and convert it into euros.
Example: The text of my descriptions is in uppercase letters. I want the first letter of each phrase to be an capital letter, whereas all the other letters will be lowercase letters.